Low ph and hard water

[k0olmini]

So I’ve posted on here numerous times saying I have high ph (based off liquid test kit). After using the co-op test strips it says I have low ph around 6.5 and hardness above 300 pm. I also don’t have a lot of buffer. Is there anything I need to be worried about with any fish species? Are there any fish species that like this kind of water? Should I use crushed coral? 

[Keeg]

You may run into issues with certain fish species. You just gotta look into fish that you want and see if they work with your parameters. If they dont and you really want a certain species of fish, then yes I would consider crushed coral because then it would be necessary to get that kind of fish. If your parameters are just slightly off compared to what the fish need in the wild, then you could try drip acclimating or starting off with their natural parameters and slowly adjust them to yours so that they are used to your parameters. It all depends on what kind of fish you want to keep. There are a bunch of fish that like your parameters but, I really enjoy livebearers, especially balloon belly swordtails. There are many different kinds, just takes a quick search on the inter webs and you got some. 

[Wrencher_Scott]

On 7/1/2022 at 1:30 PM, k0olmini said:

So I’ve posted on here numerous times saying I have high ph (based off liquid test kit). After using the co-op test strips it says I have low ph around 6.5 and hardness above 300 pm. I also don’t have a lot of buffer. Is there anything I need to be worried about with any fish species? Are there any fish species that like this kind of water? Should I use crushed coral? 

Most every fish will do good at low pH unless you are breeding. 

I would run crushed coral in the filter, it will buffer it to around 7.5 IIRC. It would make me feel better because 6.5 is way on the low side. 

I don't think I would trust that hardness reading on the strip either. 

[Marcelo]

Did you use TAP water to fill your tank ?? I am asking because I am from Florida and the tap water here is like this 300 or more ! 
 

 

[k0olmini]

On 7/1/2022 at 2:23 PM, Marcelo said:

Did you use TAP water to fill your tank ?? I am asking because I am from Florida and the tap water here is like this 300 or more ! 
 

 

I do use tap water 

On 7/1/2022 at 2:12 PM, Wrencher_Scott said:

Most every fish will do good at low pH unless you are breeding. 

I would run crushed coral in the filter, it will buffer it to around 7.5 IIRC. It would make me feel better because 6.5 is way on the low side. 

I don't think I would trust that hardness reading on the strip either. 

Oh really? I’ve used the API liquid kit and have gotten similar results. I also used it in RO water and got accurate results as well. Is there anything I need to look out for ? 

[Marcelo]

I am not saying you should do this but if you want to reduce the hardness, you can use those pillows (api softener pillow) . They work very fine *but* take care with the fishes and etc because in my tank, it reduced from about 300 GH to about 40 GH in two days and I have the feeling it was too fast ! After this, when needed, you can use RO water or Distilled water that you can find in Walmart or etc 

[Wrencher_Scott]

On 7/1/2022 at 2:34 PM, k0olmini said:

I do use tap water 

Oh really? I’ve used the API liquid kit and have gotten similar results. I also used it in RO water and got accurate results as well. Is there anything I need to look out for ? 

look out for? I just have seen weird readings from strips is all. Don't worry too much about pH. 

[nabokovfan87]

I have a "pretty hard" GH in my water, off the chart over 300 ppm. My KH has randomly dropped from 80-100 ppm down to 40-50 after moving.  As a result of this my tanks went from a PH of 6.8-7.2 down to about 6.5-6.8 and I am having issues with PH crashing if I don't change water often enough. 

As a result of this I tried to add crushed coral to my HoB and that wasn't enough.  Then I tried adding crushed coral to a ziss bubble bio air powered filter and it did not work correctly (there's a thread about it on here if you want to see full details I can grab the link to it).  Because of all this I was in a "panic" of sorts and I opted to buy some of the alkaline buffer from seachem due to it randomly being affordable (50% off, basically).

In my view you're going to need to do a few things to keep it "safe" for fish and this isn't a guarantee, but it's about your specific setup and trying to keep things as stable as possible for the fish.

1.  Extending water changes when you DO get things stable and have KH high enough will be a benefit to stability.
2.  Adding wood, botanicals, planted substrates will help to lower PH and counter balance the buffer's affect to raise KH and adversely raise PH too high.
3.  This is likely going to cause issues for shrimp and/or snails, less so issues for shrimp depending on species in question.
4.  KH may also be impacting plants, just a note, and it's something to research into.

First steps:
A. Take a sample of water from the tap and test it for KH, GH, PH.
B.  Take the same sample of water from test A and aerate it with an airstone for 24 hours, retest KH, GH, and PH.  (THIS is the value that actually matters for your tank)
C.  Compare test B to the results of your tank parameters.

Let's say your KH right now is pretty low. 0-20 ppm.  Let's say your PH is 7.5-8.0 from the tap.  Let's say you add crushed coral to the substrate (best method) and you buffer your KH slowly.  You PH might only go from 7.5 up to 7.8.  Relatively tolerable for just about everything.  If you don't add the crushed coral you can very likely see your 7.5-8.0 crash down to 6.3-6.5 without too much effort.  It's pretty much a question of how much time does that take?  That's how you'd determine how often you need to be changing water right now to keep the PH stable without modifying your KH.

Let's say your KH is buffered and your PH is stabilized slightly.  Instead of crashing every 5-7 days, you can now last up to 10-14 days.  Eventually as the crushed coral does it's thing, this will stabilize further and you can perform a water change once a month. Maintain filters and gravel vac more often, but large changes are spread out.

What I do in my case, which is similar in chemistry to your parameters in the OP, is to change my water and add a small amount of the alkaline buffer to the tank.  Seachem sells the Acid buffer and Alkaline buffer which are designed to be used in a ratio.  One raises KH+PH, one lowers PH.  Depending on your target, you'd dose this like anything else during your water change.  I used a 5G bucket and buffered it to figure out what amount would get the KH where I wanted it to be.  I have wood in the tank and other things to drop the PH so it went from 6.5 up to slightly below and slightly above 7.0.  The main thing is that PH doesn't crash on me anymore and the tank itself is pretty stable when it comes to every parameter we test for.

I do have amano shrimp in this tank and I'm dealing with a parasite issue (there's a thread in disease section where I have details).  The shrimp deaths could be associated with the KH adjustments and I've gone from targeting 80-100 for my range to targeting 50-70 for my range.  Once things are stable there, I'll try to get it up to 80.  The key thing is to do this slowly, over time, which is where the crushed coral makes it pretty easy.  If I wasn't running corydoras and running black substrate, I wouldn't mind having the crushed coral at all.

Edited July 5, 2022 by nabokovfan87
clarify GH value